Here’s a simple fix for the 6000 twisting shaft issue- just put a 1/8th inch thick dry O-Ring inside each of the locking rings. When you twist the locking rings, the o-rings compresses and tightens up between the shaft locking ring and collet keeping  the shaft sections from spinning as easily. I used these two sized o-rings (in inches): 13/16 x 1-1/16 x 1/8 3/4 x 1 x 1/8 Fully unscrew each plastic locking ring and separate each rod, leaving the plastic locking rings in place